1. Field of the Invention
The present invention relates to a speaker device including an air circulating system.
2. Description of Related Art
Conventionally, there is known an internal-magnet type speaker device including a magnetic circuit including a plane magnet, a plane plate and a pot-shaped yoke, and a vibration system including a terminal member having conductivity, a conductive damper into which a conductive member is knitted, a connecting member made of a resin material, a voice coil, a voice coil bobbin and a frame. In such a speaker device, the connecting member is mounted on the voice coil bobbin.
As the speaker device, there are known various kinds of speaker devices including radiation structure, for example.
For example, there is known a speaker device including an opening formed on an end side opposite to a bearing surface for holding a magnetic circuit made of a magnetic circuit holding member, a through hole passing through a circumferential surface of the magnetic circuit holding member, and a radiation fin formed to project in a rib state from an inner wall of the magnetic circuit holding member in order to sufficiently ensure a radiation effect of the heat generated in a voice coil (see Japanese Patent Application Laid-open under No. 2003-299185, for example).
There is also known a speaker device capable of radiating the heat generated in a voice coil with high efficiency by connecting a voice coil bobbin made of a material having thermal conductivity and radiating pipes in a state ensuring the thermal conductivity and by arranging a large number of radiation fins on an inner peripheral surface of the radiation pipe (see Japanese Patent Application Laid-open under No. 2002-78084, for example).
Further, there is known a speaker device capable of efficiently cooling the voice coil by using a material having good thermal conductivity for a bobbin (voice coil bobbin) and a center cap and by providing a slit in the bobbin (see Japanese Patent Application Laid-open under No. 2002-142292, for example).